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2019

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Full-Text Articles in Physical Sciences and Mathematics

Asymmetric Synthesis Of The C29-C34 Moiety Of Fragment A Of The Antascomicin B & Thermal Azole Based Claisen Rearrangements, Dharma Theja Nannapaneni Dec 2019

Asymmetric Synthesis Of The C29-C34 Moiety Of Fragment A Of The Antascomicin B & Thermal Azole Based Claisen Rearrangements, Dharma Theja Nannapaneni

Graduate Theses and Dissertations

The dissertation describes asymmetric synthesis towards C29-C34 moiety of fragment A of the Antascomicin B and Thermal azole based Claisen rearrangements. In chapter 1, we describes asymmetric synthesis towards C29-C34 moiety of fragment A of the Antascomicin B. The non-immunosuppressant Rapamycin, Ascomycin, and Tacrolimus (FK506), strongly binds with FKBP12, the ligand FKBP12 complexes responsible for immunosuppressive activity. Antascomicin B structurally related to Rapamycin, Ascomycin, and Tacrolimus (FK506), binds strongly to FKBP12, yet does not shown immunosuppressive activity. The ligand FKBP12 binding complexes shown to have potent neuroprotective and neurogenerative properties in mouse models of Parkinson’s disease. The linear synthesis of …


Probing Of Carbohydrate-Protein Interactions Using Galactonoamidine Inhibitors, Jessica B. Pickens Dec 2019

Probing Of Carbohydrate-Protein Interactions Using Galactonoamidine Inhibitors, Jessica B. Pickens

Graduate Theses and Dissertations

Glycoside hydrolases are ubiquitous and one of the most catalytically proficient enzymes known, and thus understanding their mechanisms are crucial. Most research has focused on the interaction of the glycon of substrates and their inhibitors within the active site of glycoside hydrolases. The inhibitors employed to probe these interactions generally had small aglycons (i.e. a hydrogen atom, amidines, small aliphatic groups, or benzyl groups). Here, the interactions of the aglycon with glycoside hydrolases are examined by probing the active sites with a library of 25 galactonoamidines. The studies described in this dissertation aim to increase the understanding of stabilization of …


Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz Dec 2019

Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz

Graduate Theses and Dissertations

Soybeans (Glycine max) are one of the major row crops in the United States, particularly in Arkansas. Soybean cyst nematode (SCN, Heterodera glycines) and southern root-knot nematode (RKN, Meloidogyne incognita) are two of the most damaging pests that cause major economic losses in soybeans. Little is known concerning the effects of common and alternative agronomic practices on nematodes in fields with nematode population densities below threshold levels. Therefore, the objective of this study was to evaluate the effects of the combination of tillage (conventional tillage and no-tillage), irrigation (irrigated and non-irrigated), wheat (Triticum aestivum) residue burning (burned and no burned), …


Detecting Differentially Co-Expressed Gene Modules Via The Edge-Count Test, Anne Gratius Lin Dec 2019

Detecting Differentially Co-Expressed Gene Modules Via The Edge-Count Test, Anne Gratius Lin

Graduate Theses and Dissertations

Background

Gene expression profiling by microarray has been used to uncover molecular variations in many different diseases. Complementary to conventional differential expression analysis, differential co-expression analysis can identify gene markers from the systematic and granular level. There are three aspects for differential co-expression network analysis, including the network global topological comparison, differential co-expression cluster identification, and differential co-expressed genes and gene pair identification. To date, most of the methods available still rely on Pearson’s correlation coefficient despite its nonlinear insensitivity.

Results

Here we present an approach that is robust to nonlinearity by using the edge-count test for differential co-expression analysis. …


An Investigation Of Metal Sulfides As The Source Of The Low Emissivity Anomaly On The Highlands Of Venus, Sara Taeko Port Dec 2019

An Investigation Of Metal Sulfides As The Source Of The Low Emissivity Anomaly On The Highlands Of Venus, Sara Taeko Port

Graduate Theses and Dissertations

Since its detection in the 1960s the source of the unusual radar emissivity signal seen on several highlands on Venus has long eluded researchers. Researchers have determined that a mineral with a high dielectric constant could explain the signal. Using a Venus simulation chamber, we experimentally investigated this enigma to build upon the candidate mineral list that has been compiled over the last several decades. We tested the stability of 8 different minerals and elements at two to three different temperature/pressure regimes in three different gas mixtures meant to simulate the conditions found on Venus for a period of no …


Studies Of Initial Growth Of Gan On Inn, Alaa Alnami Dec 2019

Studies Of Initial Growth Of Gan On Inn, Alaa Alnami

Graduate Theses and Dissertations

III-nitride materials have recently attracted much attention for applications in both the microelectronics and optoelectronics. For optoelectronic devices, III-nitride materials with tunable energy band gaps can be used as the active region of devices to enhance the absorption or emission. A such material is indium nitride (InN), which along with gallium nitride (GaN) and aluminum nitride (AlN) embody the very real promise of forming the basis of a broad spectrum, a high efficiency solar cell. One of the remaining complications in incorporating InN into a solar cell design is the effects of the high temperature growth of the GaN crystal …


Reactivity Of Photogenerated Amine Radical Cations, Qile Wang Dec 2019

Reactivity Of Photogenerated Amine Radical Cations, Qile Wang

Graduate Theses and Dissertations

Recently photoredox catalysis has emerged as a powerful tool in organic synthesis led by Professor McMillan, Stephenson, Yoon. Upon absorption of visible light, photocatalyst can be excited to its singlet state followed by intersystem crossing to form a long lived excited triplet state. While amine serves as electron donor, single electron transfer (SET) can happen between excited triplet photocatalyst and nitrogen atom on amine to give a reduced photocatalyst and amine radical cation.

Cyclopropylamines or cyclobutylamines can be oxidized by excited photocatalyst to generate amine radical cations and due to the ring strain, subsequent C-C bond cleavages can lead to …


Suitability Assessment For Integrated Urban Development In Makkah City Of Saudi Arabia, Mislat Alotaibi Dec 2019

Suitability Assessment For Integrated Urban Development In Makkah City Of Saudi Arabia, Mislat Alotaibi

Graduate Theses and Dissertations

Makkah – the third most populated city in Saudi Arabia with a population of 1,684,408 according to the 2010 demographic survey conducted by the Saudi General Authority for Statistics – is experiencing urban sprawl, which can be defined as an unplanned urban expansion that might degrade the environment and diminish the aesthetic view. This is a persisting problem in Makkah driven by multitude of processes involving the random expansion in its undeveloped land and the removal of its historic mountains surrounding Al-Masjid Al-Haram (the Holy Mosque) in an attempt to push the city limit of urban capacity within its administrative …


Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow Dec 2019

Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow

Graduate Theses and Dissertations

Slope failures in the United States alone cause millions of dollars in damage to infrastructure, threaten national monuments, create environmental hazards, and take an average of 25-50 lives a year. With the inevitable construction that occurs on slopes, it is imperative that the slopes be properly designed which requires a thorough understanding of slope grade, subsurface soil conditions, soil strength parameters, water table locations, and depth to bedrock across the entire site. The preferred method of data collection would be to use borings and other in-situ methods; however, sometimes due to cost constraints or site accessibility only a very limited …


Cost Effectiveness Of Greenhouse Gas Reductions Through Afforestation Of Agricultural Land In The Arkansas Delta, Karli A. Moore Dec 2019

Cost Effectiveness Of Greenhouse Gas Reductions Through Afforestation Of Agricultural Land In The Arkansas Delta, Karli A. Moore

Graduate Theses and Dissertations

Sequestration of atmospheric carbon in forested lands offsets carbon emissions from other industries. Conversion of private lands, particularly agricultural tracts in marginal areas, to forests can bolster carbon abatement. The United States government agencies administer some voluntary, incentive-based programs to encourage landowners to adopt production practices with positive environmental outcomes. This policy stream can be used to increase transition of marginal agricultural land to forests, thereby creating new carbon sinks. We analyze an eleven-county study area in the Arkansas Delta to determine feasibility for a subsidy focused on carbon abatement through afforestation. This study area is significant for two reasons: …


Development Of A Comsol Microdialysis Model, Towards Creation Of Microdialysis On A Chip With Improved Geometries And Recovery, Patrick Pysz Dec 2019

Development Of A Comsol Microdialysis Model, Towards Creation Of Microdialysis On A Chip With Improved Geometries And Recovery, Patrick Pysz

Graduate Theses and Dissertations

Microdialysis (µD) sampling is a diffusion-limited sampling method that has been widely used in different biomedical fields for greater than 35 years. Device calibration for in vivo studies is difficult for current non-steady state analytes of interest correlated with both inflammatory response and microbial signaling molecules (QS); which exist in low ng/mL to pg/mL with molecular weights over a wide range of 170 Da to 70 kDa. The primary performance metric, relative recovery (RR), relating the collected sample to the extracellular space concentration varies from 10% to 60% per analyte even under controlled bench-top conditions. Innovations in microdialysis device design …


Assessing The Impact Of 3d Printed Terrain On Teaching Topography In Introductory Earth Science Labs, Jay Alan Cockrell Dec 2019

Assessing The Impact Of 3d Printed Terrain On Teaching Topography In Introductory Earth Science Labs, Jay Alan Cockrell

Masters Theses

Learning to effectively read topographic maps is challenging for students, as these maps contain 3D representations of terrain displayed on a 2D surface map. This project assessed student learning when 3D terrain printed from a portion of the laboratory quadrangle map currently in use was introduced into an earth science course for non-science majors. Using a quasi-experimental design with nonequivalent groups across two semesters, performance on the Modified Topographic Map Assessment (MTMA) administered as a pre- and posttest was used to compare learning outcomes between the traditional lab and the 3D print lab intervention. Students in the traditional (n = …


Synthesis And Characterization Of Ion-Implanted Gold Nanoparticles, Nurlathifah Fnu Dec 2019

Synthesis And Characterization Of Ion-Implanted Gold Nanoparticles, Nurlathifah Fnu

Masters Theses

Gold negative ions of 70 keV energy were implanted within the quartz substrates at room temperature at seven different fluences starting from 2 x 1016 particles/cm2 to 8 x 1016 particles/cm2 with the increment of 1 x 1016. Prior to the implantation, Stopping and Range of Ions in Matter (SRIM) calculations were carried to obtain the Bragg peak below the surface of quartz. Rutherford Backscattering Spectrometry (RBS) was carried out using 2.0 MeV He++ ions to measure depth and implanted fluence of gold, and learn how they varied with fluence. Backscattered He particles …


New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd Dec 2019

New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd

Branch Mathematics and Statistics Faculty and Staff Publications

It is widely known among the Frontiers of physics, that “sweeping under the rug” practice has been quite the norm rather than exception. In other words, the leading paradigms have strong tendency to be hailed as the only game in town. For example, renormalization group theory was hailed as cure in order to solve infinity problem in QED theory. For instance, a quote from Richard Feynman goes as follows: “What the three Nobel Prize winners did, in the words of Feynman, was "to get rid of the infinities in the calculations. The infinities are still there, but now they can …


Optimal Design And Ownership Structures Of Innovative Retail Payment Systems, Zhiling Guo, Dan Ma Dec 2019

Optimal Design And Ownership Structures Of Innovative Retail Payment Systems, Zhiling Guo, Dan Ma

Research Collection School Of Computing and Information Systems

In response to the Fintech trend, an ongoing debate in the banking industry is how to design the new-generation interbank retail payment and settlement system. We propose a two-stage analytical model that takes into account the value-risk tradeoff in the new payment system design, as well as banks’ participation incentives and adoption timing decisions. We find that, as the system base value increases, banks tend to synchronize their investment and adoption decisions. When the system base value is low and banks are heterogeneous, bank association ownership maximizes social welfare. When both the system base value and bank heterogeneity are moderate, …


United States Suicide Analysis: 1999-2016, Malynn Clark Dec 2019

United States Suicide Analysis: 1999-2016, Malynn Clark

Honors Theses

The purpose of this thesis is to create information visualizations surrounding suicide trends from 1999-2016 in the United States. The original data was obtained from the Centers for Disease Control and Prevention’s Compressed Mortality Database. This database permits users to download several fields of information regarding deaths for the years given. Using this information, many graphs below show trends and patterns for suicide. One notable trend includes the higher proportion of male to female suicides for all categories explored including: age group, race, and metro/nonmetro status. The goal is to bring awareness and understanding surrounding the suicide epidemic in the …


Blockchain In Libraries, Michael Meth Dec 2019

Blockchain In Libraries, Michael Meth

Faculty Research, Scholarly, and Creative Activity

This issue of Library Technology Reports (vol. 55, no. 8), “Blockchain in Libraries,” examines the application of blockchain in libraries. Blockchain technology has the ability to transform how libraries provide services and organize information. To date, most of these applications are still in the conceptual stage. However, sooner or later, development and implementation will follow. This report is intended to provide a primer on the technology and some thought starters. In chapter 2, the concept of blockchain is explained. Chapter 3 provides eight thought and conversation starters that look at how blockchain could be applied in libraries. Chapter 4 looks …


Escape Puzzler, Shane Robertson Dec 2019

Escape Puzzler, Shane Robertson

Masters Theses & Doctoral Dissertations

This project is a systems design project. The goal of the project was to complete an online game for the purpose of entertaining an end-user. There is also additional research potential with analyzing the end-user behavior. This project showcases various skills learned at Dakota State University. This project required systems analysis, research of information technologies, database design, and project management.

About 50% of the planning phase was dedicated to scanning the IT industry for various technologies. We researched web hosting providers that would support the technologies we wanted to use. Also, a survey of available game engines was conducted. Additionally, …


Iowa Waste Reduction Center Newsletter, October 2019, University Of Northern Iowa. Iowa Waste Reduction Center. Dec 2019

Iowa Waste Reduction Center Newsletter, October 2019, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Inside this Issue:

--- Bolick Named IWRC Director
--- EPA Includes Aerosol Cans in Universal Wastes
--- Iowa EASYAir System Now Available
--- 2020-2021 Recordkeeping Compliance Calendars for Dry Cleaners
--- 2020-2021 Compliance Calendar/Logbook for Bulk Gasoline Plants
--- Industry News


Clustering Models For Topic Analysis In Graduate Discussion Forums, Mallika Gokarn Nitin, Swapna Gottipati, Venky Shankararaman Dec 2019

Clustering Models For Topic Analysis In Graduate Discussion Forums, Mallika Gokarn Nitin, Swapna Gottipati, Venky Shankararaman

Research Collection School Of Computing and Information Systems

Discussion forums provide the base content for creating a knowledge repository. It contains discussion threads related to key course topics that are debated by the students. In order to better understand the student learning experience, the instructor needs to analyse these discussion threads. This paper proposes the use of clustering models and interactive visualizations to conduct a qualitative analysis of graduate discussion forums. Our goal is to identify the sub-topics and topic evolutions in the discussion forums by applying text mining techniques. Our approach generates insights into the topic analysis in the forums and discovers the students’ cognitive understanding within …


Factors Associated With Adult Asthma Related Emergency Room Discharges In North Central Texas In 2010 - 2014, Nguyen Cao Dec 2019

Factors Associated With Adult Asthma Related Emergency Room Discharges In North Central Texas In 2010 - 2014, Nguyen Cao

Earth & Environmental Sciences Dissertations

Asthma is a common chronic disease of the airways characterized by recurrent reversible airway obstruction. More than 25 million Americans have asthma. In this study, factors associated with adult asthma related emergency room discharges in North Central Texas during the period 2010 – 2014 were investigated. This study involved a total of 78,444 cases of adult asthma hospital discharges obtained from the Dallas-Fort-Worth-Hospital Council Foundation, socioeconomic indicators from the U.S. Bureau of Census databases, and air pollution and meteorological data obtained from the Texas Commission on Environmental Quality (TCEQ). A number of important relationships underpinning asthma hospital visits in NCT …


Mathematical Modeling Of A Network Of Neurons Regarding Glucose Transport Deficiency Induced Epileptic Seizures, Ariel N. Leslie Dec 2019

Mathematical Modeling Of A Network Of Neurons Regarding Glucose Transport Deficiency Induced Epileptic Seizures, Ariel N. Leslie

Mathematics Dissertations

Epilepsy is a complex phenomena of a system of neurons simultaneously firing that are highly intensive and synchronized. Seizures are a common and well known physical feature for all types of epileptic disorders [8]. Epilepsy is known to be traced back to spatial and temporal patterns working in sequence. The rhythms, patterns, and oscillatory dynamics explain the mechanistic nature of neurons especially in absence seizures [37]. An electroencephalogram device (EEG) monitors the electrical activity within the brain using small electrodes, which measures voltage fluctuations on the scalp. Previous models such as Wilson-Cowan (1972) [34], introduced a model showing the dynamics …


Liutex Analysis By Pod And Dmd For Vortex Formations In Boundary Layer Transition, Sita Charkrit Dec 2019

Liutex Analysis By Pod And Dmd For Vortex Formations In Boundary Layer Transition, Sita Charkrit

Mathematics Dissertations

Vortices are considered as the building blocks of turbulent flows. To study how one type of vortex becomes another type especially in flow transition is one way to get better understanding about turbulence. In this dissertation, two types of vortex formations, i.e., the hairpin vortex formation and the formation of vortex structure from symmetry to asymmetry, are studied by the direct numerical simulation. According to Liu et al. (2019), Liutex has been proposed as a new physical quantity with scalar, vector and tensor forms. A Liutex vector is defined as a rotation part of fluid motion without shear contamination. The …


Some Quadratic Regular Algebras On Four Generators Wtih A 1-Dimensional Nonreduced Line Scheme, Anthony Iv Mastriania Dec 2019

Some Quadratic Regular Algebras On Four Generators Wtih A 1-Dimensional Nonreduced Line Scheme, Anthony Iv Mastriania

Mathematics Dissertations

In the 1980s, M. Artin, J. Tate, and M. Van den Bergh applied geometric techniques to noncommutative algebras. Their work introduced algebraic concepts called point modules and line modules and an associated geometric concept, which was later called the point scheme. In 2002, Shelton and Vancliff defined the concept of line scheme and developed a method for computing the line scheme of any quadratic algebra that satisfies certain conditions. Artin, Tate, and Van den Bergh were able to classify so-called quantum P²s by their point scheme; quantum P³s however are much more challenging and involve computing the line scheme. In …


A Transformative Concept: From Data Being Passive Objects To Data Being Active Subjects, Hans-Peter Plag, Shelley-Ann Jules-Plag Dec 2019

A Transformative Concept: From Data Being Passive Objects To Data Being Active Subjects, Hans-Peter Plag, Shelley-Ann Jules-Plag

OES Faculty Publications

The exploitation of potential societal benefits of Earth observations is hampered by users having to engage in often tedious processes to discover data and extract information and knowledge. A concept is introduced for a transition from the current perception of data as passive objects (DPO) to a new perception of data as active subjects (DAS). This transition would greatly increase data usage and exploitation, and support the extraction of knowledge from data products. Enabling the data subjects to actively reach out to potential users would revolutionize data dissemination and sharing and facilitate collaboration in user communities. The three core elements …


A Synthesis And Analysis Of Anhydrous Hydroxide Ion Conducting Polymer Electrolytes, Stanton Heydinger Dec 2019

A Synthesis And Analysis Of Anhydrous Hydroxide Ion Conducting Polymer Electrolytes, Stanton Heydinger

Honors Theses

This project investigates the synthesis and physical properties of polyethylene glycol monomethyl ether (MePEGn where n=3 or 7) based polymer electrolytes. The two polymer electrolytes explored in the experiments were designed from two different MePEG chains that varied in their overall length and degree of polymerization. The first MePEG backbone contained three polymerized ethoxy groups and the second contained seven. Both MePEGn polymers were modified by substituting an imidazolium group in place of the alcohol functional group at the end of the PEG chain. This modification was made to create a polymer electrolyte with an attached positive charge that could …


Online Content Consumption: Social Endorsements, Observational Learning And Word-Of-Mouth, Qian Tang, Tingting Song, Liangfei Qiu, Ashish Agarwal Dec 2019

Online Content Consumption: Social Endorsements, Observational Learning And Word-Of-Mouth, Qian Tang, Tingting Song, Liangfei Qiu, Ashish Agarwal

Research Collection School Of Computing and Information Systems

The consumption of online content can occur through observational learning (OL) whereby consumers follow previous consumers’ choices or social endorsement (SE) wherein consumers receive content sharing from their social ties. As users consume content, they also generate post-consumption word-of-mouth (WOM) signals. OL, SE and WOM together shape the diffusion of the content. This study examines the drivers of SE and the effect of SE on content consumption and post-consumption WOM. In particular, we compare SE with OL. Using a random sample of 8,945 new videos posted on YouTube, we collected a multi-platform dataset consisting of data on video consumption and …


Happy Toilet: A Social Analytics Approach To The Study Of Public Toilet Cleanliness, Eugene W. J. Choy, Winston M. K. Ho, Xiaohang Li, Ragini Verma, Li Jin Sim, Kyong Jin Shim Dec 2019

Happy Toilet: A Social Analytics Approach To The Study Of Public Toilet Cleanliness, Eugene W. J. Choy, Winston M. K. Ho, Xiaohang Li, Ragini Verma, Li Jin Sim, Kyong Jin Shim

Research Collection School Of Computing and Information Systems

This study presents a social analytics approach to the study of public toilet cleanliness in Singapore. From popular social media platforms, our system automatically gathers and analyzes relevant public posts that mention about toilet cleanliness in highly frequented locations across the Singapore island - from busy shopping malls to food 'hawker' centers.


A Mathematical Programming Model For The Green Mixed Fleet Vehicle Routing Problem With Realistic Energy Consumption And Partial Recharges, Vincent F. Yu, Panca Jodiwan, Aldy Gunawan, Audrey Tedja Widjaja Dec 2019

A Mathematical Programming Model For The Green Mixed Fleet Vehicle Routing Problem With Realistic Energy Consumption And Partial Recharges, Vincent F. Yu, Panca Jodiwan, Aldy Gunawan, Audrey Tedja Widjaja

Research Collection School Of Computing and Information Systems

A green mixed fleet vehicle routing with realistic energy consumption and partial recharges problem (GMFVRP-REC-PR) is addressed in this paper. This problem involves a fixed number of electric vehicles and internal combustion vehicles to serve a set of customers. The realistic energy consumption which depends on several variables is utilized to calculate the electricity consumption of an electric vehicle and fuel consumption of an internal combustion vehicle. Partial recharging policy is included into the problem to represent the real life scenario. The objective of this problem is to minimize the total travelled distance and the total emission produced by internal …


A Unified Variance-Reduced Accelerated Gradient Method For Convex Optimization, Guanghui Lan, Zhize Li, Yi Zhou Dec 2019

A Unified Variance-Reduced Accelerated Gradient Method For Convex Optimization, Guanghui Lan, Zhize Li, Yi Zhou

Research Collection School Of Computing and Information Systems

We propose a novel randomized incremental gradient algorithm, namely, VAriance-Reduced Accelerated Gradient (Varag), for finite-sum optimization. Equipped with a unified step-size policy that adjusts itself to the value of the conditional number, Varag exhibits the unified optimal rates of convergence for solving smooth convex finite-sum problems directly regardless of their strong convexity. Moreover, Varag is the first accelerated randomized incremental gradient method that benefits from the strong convexity of the data-fidelity term to achieve the optimal linear convergence. It also establishes an optimal linear rate of convergence for solving a wide class of problems only satisfying a certain error bound …